• This article was amended on 14 November 2013 to remove an image of the Earth First logo. There was no intention to suggest a link between Earth First and any of the terrorist attacks referred to in the article. The logo was used only because the article refers to a column in an Earth First journal 30 years ago about nanotechnology.

A chain of terrorist attacks has struck scientists in Mexico since 2011. Similar actions were taken in Switzerland in 2010 and in Italy in 2012. The Mexican attacks have been claimed by a group called Individuals Tending Towards Savagery (ITS). Their texts are littered with references to Theodore Kaczynski (the Unabomber) and expressions including "fire on nanotechnological development and on those that support it". Nanotechnology is portrayed as the cause of a future ecological catastrophe, generated by the self-replication of lethal nano-robots.

Experts say that the response to these attacks should be severe. "The answer should not be debating the terrorists on the intellectual ground, but on the moral ground: that kind of violence is simply unacceptable," says Chris Toumey, a researcher in cultural anthropology of nanotechnology at the University of South Carolina.

But where does the violence come from? The authors of the communiques are reportedly "anarcho-primitivists", a subculture that arose in the 1990s when anarchism crossed with radical environmentalism. It calls for overthrowing of industrial civilisation and a return to a primitive lifestyle. One of its references is writer Derrick Jensen, who called for "deep green resistance".

"[ITS's] language very much resembles long-standing rhetoric from the green anarchist subcultures in the US," says Bron Taylor, professor of religion and nature at the University of Florida, with 25 years' experience of ethnographic research about the terror movements.

"I do find interesting echoes of something we saw in the 90s: the alliance among deep ecology activists and anti-capitalists groups in the context of the anti-globalisation protests," says Steve Jones, a literary historian at Loyola University Chicago, and an expert in luddites, a 19th-century group of English artisans who protested against new industrial textile machines by smashing them. Radical environmentalists are often "involved in reading the luddites into the contemporary situation", he says.

The reference publication of the movement in the 80s, the Earth First journal, featured a column called Ask Ned Ludd, in reference to the mythical character that gave name to the luddites. Jones thinks that neo-luddites are in fact misreading the original luddites, but he believes that understanding the difference between the old and modern ones tells us a lot about the ideology of the latter.

"Luddites were not anti-technology: they were skilled craftsmen, involved in a labour movement aimed at keeping their machines and their jobs," he says. "That's very different from the neo-luddites ideas of relinquishing civilisation and [of] nature as the supreme good."

Jones thinks neo-luddism is fed rather by "the idea of technology as a disembodied, transcendent, terrifying force outside the human", which emerged in the mid 20th century, with the bomb and the rise of large-scale computing.

Taylor says what struck him from his fieldwork was a "sense that nature is sacred, deep ecological ethics in which all living things have inherent value … what struck me right from the beginning [of my fieldwork] was the extent to which religious terminology was deeply infused in radical environmental subculture". At one time, anarchism had very little environmental concern, he argues, but over the past few decades this ideology has resorted to indigenous cultures and their relation with nature, as an alternative to what they perceive as the "totalitarian nation state".

But why are anarcho-primitivists specifically targeting nanotechnology? One of ITS's texts says "nanotechnology is the furthest advancement that may yet exist in the history of anthropocentric progress". Jones says: "Nanotechnology takes place at invisible scales, so that it adds to this sense that technology is apart from us."

Taylor adds: "Radical environmentalists have a strong suspicion that western science divides people from the natural world and promotes an ideology of human superiority."

However, there may be a deeper driver, related to how nanotechnology has been represented. "ITS's statements reference the 1985 book, Engines of Creation, by [engineer Eric] Drexler", Chris Toumey points out. This text forecasts an almost infinite potential for nanotechnology, including steering human biology artificially – a utopian idea known as trans-humanism. But it envisages also a possible "grey-goo" scenario, in which self-replicating robots take over nature and society, consuming everything as they go, turning it all into a grey mush.

"ITS gives credibility to that by saying that Drexler was one of the greatest scientists in history: in fact, not a single nanotechnology scientist thinks that grey-goo is plausible," says Toumey. "The idea of a kind of convergence of human and machine looks today both oddly optimistic and exaggeratedly dystopian," Jones points out.

"How is it that a group is serious enough to send pipe bombs to murder scientists for their work in nanotechnology, but not serious enough to learn about nanotech beyond what they find in Eric Drexler's stories?" writes Toumey in a recent op-ed in Nature Nanotechnology. "ITS is incredibly naive about nanotechnology. It's foolish to use terrorism, but it is especially foolish to do it knowing so little."